Ambulance ventilation system



April 23, 1946.

E. L. SCHOFIELD AMBULANCE VENTILATI'ON 4SYSTEM Filed Feb. 27, 1943 ventilation Patented Apr. 23, 1946 UNITED STATES PATENT Aolf-Fics.

AMBULANC VENTILATIoN SYSTEM tion of Delaware Application February 27, 1943, SeralNo. 477,471

3 Claims.

This application is a continuation in part of my copending application Serial No. 426,985, filed January 16, 1942.

This invention relates to a new and improved system especially designed and adapted for use in an ambulance, but also suitable for other vehicles.

The principal object of my invention is to provide a system whereby fresh air in warm weather may be introduced from a full length air duct in the top of the vehicle having a fresh air intake at the forward end forming a scoop-like projection above the cab portion, the fresh air discharging downwardly from the duct through openings distributed lengthwise ofthe bottom of the duct and being discharged under, around, and between the rear doors of the vehicle, a shut off valve being provided for the fresh air intake,'to be closed in 'cold weather, and a ventilator being provided in the top wall of the air duct arranged to be opened in cold weather inclined in such relation to the movement of the vehicle so that foul air will be exhausted from the aforesaid air duct, the foul air being collected through the aforesaid openings distributed lengthwise of the bottom of the air duct, fresh air under these operating conditions being taken in through a cowl ventilator and heated at or near the point of intake.

Another object of the invention is to provide stretcher carriers suspended from the top of the ambulance on pivoted arms swingable as a pendulum relative to the top for movement of the carriers from an extended loading and unloading position to a retracted position for transportation, and movable, furthermore, with the arms upwardly to an out-of-the-way position in a recess in the top under the full length air duct, the carriers having bottoms provided with openings distributed lengthwise thereof 'thro-ugh which air may pass freely when the carriers are disposed in the folded out-of-the-way position, whereby to permit substantially as good ventilation under those conditions as otherwise, this being particularly important in an ambulance for civilian defense use, because when the ambulance is not beingfused for taking injured to the hospitals, it is used in the evacuation of children and old people from areas under bombardment and is equipped for that purpose with full length seats on opposite sides of the body, foldable to out-ofthe-way positions along the side walls.

The invention is illustrated in the accompanying drawing, in which- Fig. 1 is a vertical longitudinal section through an ambulance embodying my invention, the sectionbeing taken on the line -I--I of Fig.`2;', Fig. 2 is a cross-section of Fig. 1, taken on the line 2-2 thereof, and

Fig. 3 is an enlarged sectional detail of a portion of Fig. 1.

The same reference numerals are applied. to corresponding parts throughout these views'j The ambulance shown in Figs. 1 and 2, as disclosed in the parent application, is adapted to support two standard Red Cross lor Army type stretchers IU side by side on theoor II; `Two other stretchers I0 can be supported on carrier racks I2, referredto hereinafter as carriers, suspended from the top. I3 on pendulumtypearms `I4. These' arms are swingable fromfthe fullline position for transportationof the stretchers to the dotted line position indicated in Figgl to have the carriers I2 project through the rear door opening far enough for easy loading and unloading of the stretchers carried thereby. The'arms I4 are long enough to provide notonly for Suni- 'cient extension' of" the two carriers I2 from the rear of the ambulance in the loading positiomhut also for support of the carriers at an aelevation low enough 'for easy loading' of patients by inexperienced average size men and women standing behind the ambulance. A latch is indicated at I6 and is provided in connection with each carrier in the rear end of the body'to cooperate with locking plates I1 and I8 for quickly releasably Alocking the carrier in either of the two positions 4is most important in the handling ofthe sick and injured, and it should also be clear thatthere is no necessity for the attendant entering the ambulance in the loading or unloading. Any one of the four patients in a` fully' loaded ambulance `cancbe removedwithout disturbing any of 4the lothers and without requiring an .attendant to enter the ambulance. There areftwo doors IS, hinged as atf20, to close the rear end of the ambulance, and thereis a rear step 2| which is more or less covered and protected by the' doors I9 when closed. This is a convenient entry step, the tread portion of which is level with the top of the rear bumper22. j Y

' wise relative to the body of the ambulance".

In addition to the drivers seat 23 in the front Cab portion 24, there is another front seat along side it (not shown), which is movable to an outof-the-way position to permit attendants to enter or leave the ambulance through the right hand front door 25. Two seats 26 on opposite sides of the ambulance behind the front seats are for nurses or attendants when theambulance is being used'l for: carrying; sick and injured; There are two full length seats 21 behind the attendants seats 26, which can be swung down from the, sides of the ambulance and made available for use when the ambulance is to be usedfor'example, in the evacuation of children andold people from areas under bombardment. 'IheistretchersJ ID under those conditions are stored in the compartments 28 under the floor Il extending cross- Thel carriers I2, or either of them, can be movedup wardly into recesses 29 provided therefor in the top` I3, asl` indicated. in; the'` left. hand. portion. of Fig. 2; the. pendulum typeIv arms 141i being; foldable upwardlyr into :the recesses .zawwithithe carriers I2, and. when the carriers are moved-:toithisout-oi.- the-wayposition; the bottoms 30thereof arev substantially ilush with the inside of the top; as shouldi. be clear from Figs;Y L and 2.. Suitable latchA means (not.y shown): are provided'. operable by meansioffthefthumb-piece 3l: tolock; the carriersf releasably in the out-of-the-way. position. The carriersY are'. pivot'ed to fthe 1 lower endsv ofthe arms at; 32, and; thearms arepiVOted' in the top' of the ambulance at 33; andsuit'able spring means (not shown are provided'f'or Ycounterbalancingf the: weight of4 the carrier assemblies, so

thatwlien'the'=latcliesf 31 'arezreleas'edf the carriers will' not drop freely" by gravity but can. be moved downwardly` easilytotheoperatin'g.. position. On

thefotherhanen. in the return. of: thel carriers tor foldd' ouii-oftlie"-wayy position, the counterbalaimingy means` facilitatethis operation. The sheet metallbottomslmly of the carriershave longitudinally extending channel-l side members 34 secured?! thereon. providing convenient: guides for the legs4 3 dof therstretchersini sliding .the 'stretchersi. td' andi fro. im loading and unloading, and these channels arev of? great. advantage because onceA the front pairl of legs.v onA a'v stretcher have been` enteredV in theV channels thev stretcher is guided from that'pointon, as:` the legs slide along the channels; and ititherefore requiresonly one attendant to completelthe loadingof a stretcher after' the front legs: have been entered in the channels: by other attendants.. Somucli for a genera-l;- descriptioniof the type of ambulance to whichrtlrefventilation systemroi" my inventionihas beeirapplied;

36 indicates al longitudinally` extending. air duct in. .the middlei oi the; top` i3: of." the ambulance, whiolnprojectsf forwardly over. the top=of the driver'scabld and has an inletgrill 31." inthe front end. thereof? forA intake of fresh: air in warm weather; Ther air' passing through the grill 31 enters-the'duct 33througha louvered opening 38 behindtheigrilhwhich can-.bei opened or closed at will. by an. attendant'. inside the ambulance by operating a ap valve39fpivotedlatits upper end at 40 and?pivotal]yconnect'edatl its lower end-to a rodsilI-t which hasa: push and( pull knob42 on the rear' end;r thereof,. the` rodi extending rearwardly fronrthe'ap-.valveriover'thetop of the cab 24 andthrough an openingY 43 into-the upper front portion.- or thev ambulance, where the' knob 4'2 is easily-accessible to either of the attendants seated in the seats 26. Notches Mandi-45 are provided in the bottom of the rod 4l in longitudinally spaced relation to permit locking the ap valve 39 in an adjusted position by engagement of a locking plate 46 in either of these notches. The grilled front end 31 of the air duct 36 serves as a scoop to take in fresh air readily in the forward travel of the ambulance, and the top wall 41 of the cab 24-isconformedwithin the front end portionV off the. air duct 36 to provide upwardly inclined portions 48 and 49 to direct the incoming air upwardly over the transverse wall 5B through which the push and pull rod 4| extends, whereby to minimize the resistance to air flow in the duct and insure a iiow of air at reasonably high velocityv ihsidethe duct lengthwise of the top of the stretcher-or passenger space 5l. There is an inner top wall or panel 52 in each of the recesses 29, the marginal portion of which extends across the bottom of the air duct 36, and each of these walls 52 has longitudinally spaced holes 53 provided therein so that-air can beV discharged downwardly into-the spaceV 5+ readily/from the duct 36. A partition 63 extends lengthwise of the middle of theductrfrom a point behind the inclined end 49 of the top'wall 4i: ofl the cab, soas to dene two passages'l. and 68- on opposite sidesthereo for substantially even distribution' ofthe incoming air. to-thetwo-halves of the space 5l. The partition; 5E.v also separates thetwo' recesses 29 in which the two carriers. |72- are adapted. to be housed. l/Vhen the carriers l2 are in:use, as indicated in the right hand portion ofv Fig. 2, airis discharged'throughthe holes 53directly into the space 5l, but when. the.` carriers are folded in out-of-the-way position, as; shown in the left handportion ofv Fig. 2, the air discharged through the holes 53 is causedto ilow throughotlier holes 54 provided in longitudinally spacedv relation in the bottom 390ithe carrier. The'air ultimately finds its way out-through the rear opening l5 between, around, and-under the doors I9.. The general.- direction ofthe air flow is indicated by the arrows a. There isn-o sensation of draft with this kind of ventilation, due to the fact that there isnosuddeninrush. of air atany. one point but instead adiffusionover the entire area of the top of. the. ambulance. as the air seeps through the multiplicity ofv openings 53, or 53 and 54, as the case may be. rIlhere is no need. for any. blowers orsuction. fans to induce the circuation described, sulcient pressurebeing produced in the manner of` pick-up ony the one hand and. there being` a suicient suction behind. the ambulance in itsforward travel. to induce outlow of stale air through therear opening, l5 around, between, and under the doors I9.

In cold weather, the flap Valve 39 is kept closed andfresh air is admitted by opening the conventional cowl'ventilator, 55. The air. thusadmitted can becirculatedY through or past the usual hot water or other type` heater in the drivers cab 24, like' that indicated at 56, and circulated rearwardly into thev passenger or stretcher space 5l. The: motor` driven fan 5? of the heater insures good" circulation of the warm air. Under certain conditions, as, for example, where there is only one patient being carried on a stretcher, the seepage of air through. the rear opening l5 around, between, and under the doors I `Swill suffice to provide. good ventilation. However, a damper or ventilator 58 is pivoted at 59 in the air duct 36 to serve asa closure for an opening 6B in the top wall of the air duct located adjacent the front end of the. passenger and stretcher spacel. This damperopens upwardly and forwardly to the inclined position shown, whereby in the forward travel of the ambulance there is sufficient suction to exhaust foul air from the top of the space l through the openings 53, alone or through the openings 53 and 513, the foul air going through these openings being conducted through the duct 36 forwardly and out through the opening Sil, where it is entrained with the air flowing past the top of the damper 58. The dotted line arrows b indicate the circulation of air from the point of entry at 55 to the point of exit at The damper 5t has an arm 5I attached thereto and extending downwardly therefrom through the opening Se. A push and pull rod 62 is pivotally connected to the lower end of the arm El and extends through the opening t3 in the wall 50 in paraliel relationfto the rod previously mentioned. A knob 63 is provided on the rear end of the rod, and there are two notches 'ii and B5 in the rod on the lower side thereof for engagement of the locking plate 46 in either notch to hold the damper in opened or closed position.

It should be apparent from the foregoing description that I have provided a ventilation system for year around operation, which does not involve a complicated or expensive construction. Full advantage is taken of the air flow over the 'top of the ambulance to induce an ample supply of fresh air through the passenger space 5I in warm weather operation and also in cold weather operation, and full advantage is also taken of the suction created behind the vehicle in the movement thereof to exhaust stale air in warm weather operation and also at certain times in cold weather operation, although the damper 58 will usually be opened to insure proper exhausting of foul air in cold weather operation. Incidentally, in cold Weather operation, the fact that air from the heater 5S is directed along the floor is an advantage, because it is well recognized that it is most important to keep the feet warm for best comfort ir; cold weather ventilation. The forced circulation of air downwardly along the oor avoids any danger of the incoming air at 55 taking a short out rearwardly and upwardly through the openings 53 and 54 and out through the ventilator opening Gt, without circulating around the feet of the driver and passengers.

It is believed the foregoing description conveys a good understanding of the objects and advantages of my invention. The appended claims have been drawn to cover all legitimate mcdications and adaptations.

I claim:

l. In a motor vehicle ventilation system, the combination of a closed body having a drivers cab portion in open communication with the space therebehind and provided with a fixed windshield and containing a heater, a variably openable cowl ventilator on the front of the cab for adjustable intake of fresh air for circulation rearwardly through the cab into the body whereby such fresh air may be heated by the heater, a longitudinally extending air duct on the top of said body having communication with the inside of the body throughout a substantial portion of the length of the top thereof through a multiplicity of closely spaced openings provided therein substantially throughout the area thereof, the front end portion of said duct extending transversely over the top of the cab and ending in a scoop-like fresh air inlet, an exhaust opening in the front end portion of said duct in rearwardly spaced relation to said inlet, manually operable valve means for regulating or shutting oli the inflow of air through said fresh air inlet, and an adjustable Ventilating closure for said exhaust opening extending upwardly and rearwardly from the front edge ofsaid exhaust opening for variably uncovering the exhaust opening for outflow of air, the closely spaced openings in said duct affording uniform ventilation of the body by downflow of fresh air therethrough when the inlet opening is opened and the exhaust opening is closed, and said closely spaced openings tending to promote uniform heat distribution in and ventilation of said body by upow of heated air therethrough when the cowl ventilator is opened and the heater is in operation and the inlet opening is closed and the exhaust opening is opened.

2. In a motor vehicle ventilation system, the combination of a body havingY a top wall over the passenger space in said body, an air duct extending lengthwise with respect to said top and having a `forward air inlet opening adapted to take in air from the stream of air flowing over the top of said body when the vehicle is moving forward, a perforated inner top wall for the vehicle through which air may be discharged from the air duct into the upper portion of the passenger space in said body, a manually adjustable shutter for the air inlet opening, said duct having an exhaust opening in its outer top wall at one of the ends thereof, and a manually adjustable damper for closing said exhaust opening, which in its open positions extends upwardly and rearwardly from the front edge of said exhaust opening into the stream of air flowing over the top of said body when the vehicle is moving forward, said damper being adapted to variably uncover the exhaust opening for outlet of air and being operable independently of said shutter.

3. In a motor vehicle ventilation system', the combination of a closed body, a longitudinally extending air duct on the top of said body having communication with the inside cf the body throughout a substantial portion cf the length of the top thereof through a multiplicity of closely spaced openings provided therein substantaliy throughout the area thereof, the front end portion of said duel; ending in a scoop-like fresh air inlet portion extending transversely over the top of the cab, an exhaust opening in the front end portieri of said duct over the cab and in rearwardly spaced relation to said inlet, manually operable valve means for regulating or shutting olf the inflow of air through the inlet opening, and an adjustable Ventilating closure for said exhaust opening extending upwardly and rearwardly from the front edge of said exhaust opening for variably uncovering the exhaust opening for outflow of air, the closely spaced openings in said duct affording uniform ventilation of the body by downflow of fresh air therethrough when the inlet opening is opened and the exhaust openn ing is closed, and said closely spaced openings tending to promote ventilation of said body by upow of air therethrough when the inlet opening is closed and the exhaust opening is opened.

' EARL L. SCI-IOFIELD.` 

